During the First and Second World Wars, many members of the corps commanded battalions and brigades in the New Zealand Expeditionary Forces sent overseas.

Each Dominion was expected to be capable of raising an expeditionary force with units organised along the lines of the British Army.

[6] This was expected to considerably increase New Zealand's military capability to around 30,000 men, with 10,000 being able to rapidly mobilise as an expeditionary force in an emergency.

[8] Some officers of the New Zealand Staff were to be graduates of the Royal Military College in Australia, to which ten cadets were to be sent annually.

[8] To make up the numbers, Major General Alexander Godley, the new commandant of the New Zealand Military Forces, held a training camp in early 1911.

[9] During the First World War, many of the officers of the Staff Corps volunteered for and served in key leadership positions in the New Zealand Expeditionary Force (NZEF), often as battalion and brigade commanders.

[9] After the war, greater integration between the professional military and the Territorial Force saw the need for the New Zealand Staff Corps diminished.